I had trouble figuring out the NAT firewall on my router when I first got it. Finally gave up, and put my PC in the DMZ, and used a software firewall (Firestarter). Eventually decided it wouldn't allow me to do some packet filtering I wanted. In the process of replacing it, I discovered how to use the NAT firewall, and now have it doing everything I want ... except one thing.

In Firestarter, I could view information about each currently active connection ... Servers I was accessing, Users on my FTP server, My mail connection, HTTP connections via a browser, etc. Info consisted of the remote IP address, port connection, and service. If my NAT firewall provides that info, I haven't been able to find it.

Is there a netstat flag, or some other method of displaying this info?

There's a couplt of things you'll probably enjoy:
1) iptstate
2) netstat
3) iptraf

The first two are commands so you should man them. The last is a simple program with a simple interface but is very helpful for monitoring connections in real-time.

Ooh! iptraf does exactly what I want without any setup whatsoever. Plus it looks like it'll do lots more after I read the instructions.

I know.... I LOVE it Best part is: It works over ssh.

Glad this info was of help.

I often use netstat -an --inet for this. Or, just netstat -A inet. Another helpful one is netstat -pultw which lists all connections both tcp and udp.